Date:         Mon, 13 May 1996 14:51:41 CST6CDT
Sender:       Vanagon Mailing List <vanagon@vanagon.com>
From:         "Dan Houg" <fairwind@northernnet.com>
Subject:      Re: Re- Continuing Engine Troub



> On 13 May 1996, Harvey Chao wrote:

> > I have a modest concern about this.  In essense you are probing a very high
> > impedence input channel with an ohmeter.  Depending upon the meter and
> > resistance range selected on the meter, such action imposes a voltage into
> > this input channel that may not be compatible with the circuit under test. 
> > Without know the components, meter, and circuit,  there is some potential risk
> > of damage in this process.

Harvey-
Well, since i was the one that subjected my ecu to the proding and 
probing of a disrespectful ohm-meter, i'll comment  :)

i thought of this concern too and probably would not have done it if 
i had just an analog meter.  i used a Fluke 78 digital multi-meter 
and these are supposed to have an extremely high impedance when 
checking voltages and also be very 'easy' on components when checking 
resistance.  i don't have the specs for the forward voltage in 
resistance mode, however.  since the O2 sensor itself generates a 
voltage i figured i would be pretty safe testing this particular 
circuit.

-dan